Four goals inside 17 minutes set St Mary’s on the path to full points.
The Saints ultimately eased past Ballymacash Rangers by 5-0 despite a depleted side.
Ruairi Feeney grabbed two goals, alongside Joe McKeever and Ryan Creaney. Johnny Stewart wrapped up the rout.
“We have improved on last season’s tally of points,” said St Mary’s manager Conor Hagan. “Our target is a top-four finish.”